This invention relates generally to an electrostatographic printer or copier, and more particularly concerns a cleaning apparatus having an air removal system for waste removed from a brush detoning roll.
In an electrophotographic application such as xerography, a charge retentive surface (i.e., photoconductor, photoreceptor or imaging surface) is electrostatically charged, and exposed to a light pattern of an original image to be reproduced to selectively discharge the surface in accordance therewith. The resulting pattern of charged and discharged areas on that surface from an electrostatic charge pattern (an electrostatic latent image) conforming to the original image. The latent image is developed by contacting it with a finely divided electrostatically attractable powder referred to as "toner". Toner is held on the image areas by the electrostatic charge on the surface. Thus, a toner image is produced in conformity with a light image of the original being reproduced. The toner image may then be transferred to a substrate (eg., paper), and the image affixed thereto to form a permanent record of the image to be reproduced. Subsequent to development, excess toner left on the charge retentive surface is cleaned from the surface. The process is well known, and useful for light lens copying from an original, and printing applications from electronically generated or stored originals, where a charge surface may be imagewise discharged in a variety of ways. Ion projection devices where a charge is imagewise deposited on a charge retentive substrate operates similarly.
Although a preponderance of the toner forming the image is transferred to the paper during transfer, some toner invariably remains on the charge retentive surface, it being held thereto by relatively high electrostatic and/or mechanical forces. Additionally, paper fibers, Kaolin and other debris have a tendency to be attracted to the charge retentive surface. It is essential for optimum operation that the toner remaining on the surface be cleaned thoroughly therefrom.
A commercially successful mode of cleaning employed on automatic xerographic devices utilizes a brush with soft conductive fiber bristles or with insulative soft bristles which have suitable triboelectric characteristics. While the bristles are soft for the insulative brush, they provide sufficient mechanical force to dislodge residual toner particles from the charge retentive surface. In the case of the conductive brush, the brush is usually electrically biased to provide an electrostatic force for toner detachment from the charge retentive surface.
After cleaning the charge retentive surface (i.e. imaging surface), a common method of cleaning the brush fibers is by utilizing a detoning roll. Currently the biggest problem associated with roll detoning is the reliability of the augering system used to remove the toner from the biased detone rolls. The heat generated by the augers blocks the toner and the technical representative often has to completely replace the cleaner assembly.
The following disclosure may be relevant to various aspects of the present invention and may be briefly summarized as follows:
U.S. Pat. No. 4,989,047 to Jugle et al. discloses the removal of debris and toner removal from the cleaning housing is by an auger arrangement which respectively moves debris to a storage area for subsequent removal and toner to the developer station for reuse. Additionally, there is an air stream for toner and debris removal.
U.S. Pat. No. 5,031,000 to Pozniakas et al. discloses the removal of debris and toner removal from the cleaning housing is by an auger arrangement which respectively moves debris to a storage area for subsequent removal and toner to the developer station for reuse. Additionally, there is an air stream for toner and debris removal.